How exactly String Pool Works in Java?

Kumar Saurav

4 min read

·

Jun 15, 2026

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Let me deep dive in to make you understand back story.

Have you ever wondered why these two lines return true?

String a = "java";
String b = "java";
System.out.println(a == b);

And then this one returns false?

String a = new String("java");
String b = new String("java");
System.out.println(a == b);

Same text. Different result. Same language. Different behavior.

So what is Java really doing behind the scenes?

The answer is the String Pool.

Think of it like a shared shelf

Imagine a library where popular books are kept on a special shelf.

If ten people ask for the same book, the library does not print ten separate copies. It gives everyone a reference to the same book.

That is exactly how Java handles string literals.

When you write:

String s1 = "hello";

Java first checks the String Pool.

• If "hello" already exists there, Java reuses it.
• If it does not exist, Java creates it and stores it in the pool.

So when you write:

String s2 = "hello";

s2 points to the same pooled object as s1.

What exactly is the String Pool?